A wastewater purification device for semiconductor micropore fabrication

Abstract

This utility model relates to the field of semiconductor processing and discloses a wastewater purification device for semiconductor micro-hole processing. The device includes a wastewater tank, a powder feeder, a powder mixing mechanism, a first delivery pump, a filter, a clean water tank, a liquid constant-temperature cooler, a second delivery pump, an accumulator, and a pressure regulating valve. The wastewater tank has a wastewater inlet. The powder feeder is located outside the wastewater tank, and its output end is connected to the inside of the wastewater tank. The wastewater tank is equipped with a powder mixing mechanism and is connected to the filter via the first delivery pump. The output end of the filter is connected to the clean water tank, which is equipped with a liquid constant-temperature cooler. The clean water tank is connected to the accumulator via the second delivery pump, and the accumulator is connected to the pressure regulating valve. The advantages of this utility model are: it can reliably filter wastewater generated during micro-hole processing and ensure that the filtered clean water quality, temperature, and pressure meet the requirements for use with micro-hole processing water-cooled drill bits.

Description

Technical Field

[0001] This utility model relates to the field of semiconductor processing technology, specifically to a wastewater purification device for semiconductor micropore processing. Background Technology

[0002] Semiconductor microvia fabrication refers to the process of creating sub-millimeter to micrometer-sized holes in semiconductor materials, packaging substrates, or related components to meet the needs of high-density interconnects, chip testing, and advanced packaging. To achieve microvia fabrication, machine tools and microvia water-jet drills are deployed in the machining center. These drills spray water in real-time during the process to meet requirements such as cooling and impurity removal, while the machine tools collect the wastewater generated during processing.

[0003] Because micro-hole drilling bits emit water from the center, and the micropore diameter is typically only 0.15mm, or even smaller, they require extremely high-quality clean water that undergoes high-precision filtration. If the filtration level does not meet the specified requirements, the micro-hole drilling bit is prone to clogging, affecting processing quality. Furthermore, micro-hole drilling bits have high requirements for water temperature and pressure. Therefore, the wastewater generated during processing is completely unsuitable for the use of micro-hole drilling bits. Directly discharging this wastewater would not only be wasteful but also pollute the environment. Therefore, there is an urgent need for a wastewater purification device that can reliably filter the wastewater generated during micro-hole processing and ensure that the filtered water meets the requirements for the use of micro-hole drilling bits in terms of quality, temperature, and pressure. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this utility model provides a wastewater purification device for semiconductor micro-hole processing, which can reliably filter the wastewater generated during the micro-hole processing process and ensure that the filtered clean water quality, temperature and pressure meet the requirements for use with micro-hole processing water-cooled drill bits.

[0005] To achieve the above objectives, this utility model provides the following technical solution: A wastewater purification device for semiconductor micropore processing includes a wastewater tank, a powder feeder, a powder mixing mechanism, a first delivery pump, a filter, a clean water tank, a liquid constant temperature cooler, a second delivery pump, an accumulator, and a pressure regulating valve. The wastewater tank has a wastewater inlet. The powder feeder is located outside the wastewater tank, with its output connected to the inside of the wastewater tank. The wastewater tank is equipped with the powder mixing mechanism and is connected to the filter via the first delivery pump. The output of the filter is connected to the clean water tank, which is equipped with the liquid constant temperature cooler. The clean water tank is connected to the accumulator via the second delivery pump, and the accumulator is connected to the pressure regulating valve. The filter is a stacked plate and frame filter with a built-in precision filter membrane. The powder feeder is used to add diatomaceous earth powder, which has adsorption, bridging, and agglomeration effects and forms a dynamic filter cake layer on the surface of the precision filter membrane of the filter, into the wastewater tank.

[0006] Furthermore, it also includes a first level gauge installed in the sewage tank and a second level gauge installed in the clean water tank.

[0007] Furthermore, the filter is a stacked plate and frame filter with a built-in polymer precision filter membrane with a nominal precision of 0.1μm.

[0008] Furthermore, the second delivery pump is a cooling water pump.

[0009] Furthermore, the first delivery pump is a diaphragm pump.

[0010] Furthermore, the sewage tank is provided with a drain outlet at the lower end and an overflow outlet at the upper end.

[0011] Furthermore, the sewage tank and the clean water tank share a main tank, which is divided into two independent storage spaces by a partition. One independent storage space serves as the sewage tank, and the other independent storage space serves as the clean water tank.

[0012] Furthermore, the powder mixing mechanism includes a drive motor, mixing blades, and a mixing shaft; the drive motor is located above the sewage tank, the mixing blades are located in the lower middle part of the sewage tank, the upper end of the mixing shaft is connected to the output end of the drive motor, and the lower end of the mixing shaft is connected to the mixing blades.

[0013] Furthermore, it also includes a control cabinet; the powder feeder, powder mixing mechanism, first conveying pump, filter, liquid constant temperature cooler, second conveying pump and pressure regulating valve are electrically connected to the control cabinet.

[0014] By adopting the above-mentioned technical solution of this utility model, at least the following beneficial effects are achieved: By adding diatomaceous earth powder to the sewage tank using a powder adding machine, and mixing the diatomaceous earth powder and sewage in the sewage tank using a powder mixing mechanism, and then using a first conveying pump to transport the mixed sewage to a stacked plate and frame filter for filtration, the filtration level can reach 0.01um; at the same time, the clean water in the clean water tank is kept at a constant temperature using a liquid constant temperature cooler, and the output clean water is first stabilized by an accumulator, and then the outlet water pressure is controlled by a pressure regulating valve; therefore, by adopting the above-mentioned technical solution of this utility model, the sewage generated during the micro-hole processing can be reliably filtered, and the water quality, water temperature and water pressure of the filtered clean water can meet the requirements of the micro-hole processing water drill bit. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the wastewater purification device for semiconductor micropore processing according to the present invention. Figure 2 This is one of the three-dimensional structural diagrams of a wastewater purification device for semiconductor micro-hole processing according to this utility model, in which the wastewater tank and the clean water tank share a main body; Figure 3 This is the second three-dimensional structural diagram of a wastewater purification device for semiconductor micro-hole processing according to this utility model, in which the wastewater tank and the clean water tank share a main body; Figure 4 This is a cross-sectional view of a wastewater purification device for semiconductor micropore processing according to this utility model, in which the wastewater tank and the clean water tank share a main body.

[0016] Figure label: Wastewater purification device 100; Wastewater tank 1, wastewater inlet 101, wastewater outlet 102, overflow outlet 103; Powder feeder 2; Powder mixing mechanism 3, drive motor 301, mixing blade 302, mixing shaft 303; First delivery pump 4; Filter 5; Clean water tank 6; Liquid constant temperature cooling machine 7; Second delivery pump 8; Accumulator 9; Pressure regulating valve 10; First liquid level gauge 11; Second level gauge 12; Main body 13, partition plate 131; Control cabinet 14. Detailed Implementation

[0017] The technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0018] Please see the appendix Figures 1 to 4 As shown, this utility model provides a wastewater purification device 100 for semiconductor micro-hole processing. The wastewater purification device 100 includes a wastewater tank 1, a powder feeder 2, a powder mixing mechanism 3, a first conveying pump 4, a filter 5, a clean water tank 6, a liquid constant temperature cooler 7, a second conveying pump 8, an accumulator 9, and a pressure regulating valve 10. The wastewater tank 1 is used to temporarily store wastewater (i.e., cutting fluid) generated during semiconductor micro-hole processing and after preliminary filtration. The powder mixing mechanism 3 is used to mix the added diatomaceous earth powder with the wastewater to ensure that the diatomaceous earth powder can better adsorb impurities in the wastewater. The first conveying pump 4 is used to transport the mixed wastewater from the wastewater tank 1 to the filter 5. The clean water tank 6 is used to temporarily store the clean water output from the filter 5. The liquid constant temperature cooler 7, a second conveying pump 8, an accumulator 9, and a pressure regulating valve 10. The liquid constant temperature cooler 7 is used to control the temperature of the clean water in the clean water tank 6, so that the clean water tank 6 can provide clean water at a constant temperature. The liquid constant temperature cooler 7 is a commonly used industrial temperature control device in the prior art. Its specific structure and working principle are well known to those skilled in the art, so the liquid constant temperature cooler 7 will not be described in detail here. The second delivery pump 8 is used to deliver the clean water in the clean water tank 6 to the accumulator 9. The accumulator 9 is used to stabilize the pressure of the clean water output by the second delivery pump 8. The pressure regulating valve 10 is used to control the outlet pressure of the clean water. The filter 5 is a stacked plate and frame filter with a built-in precision filter membrane. The powder adding machine 2 is used to add diatomaceous earth powder with adsorption bridging and agglomeration effects and to form a dynamic filter cake layer on the surface of the precision filter membrane of the filter 5 into the sewage tank 1.

[0019] The wastewater tank 1 is equipped with a wastewater inlet 101, which is used to input wastewater generated during the microporous processing and after preliminary filtration into the wastewater tank 1. A powder feeder 2 is located outside the wastewater tank 1, and its output end is connected to the inside of the wastewater tank 1 to add diatomaceous earth powder into the wastewater tank 1. In specific implementations, this invention can either automatically add diatomaceous earth powder to the wastewater tank 1 by timed control or be manually operated. The wastewater tank 1 is equipped with a powder stirring mechanism 3 to mix the wastewater and diatomaceous earth powder in the wastewater tank 1. The algae mud powder is stirred and mixed. The sewage tank 1 is connected to the filter 5 through the first conveying pump 4, so that the sewage in the sewage tank 1 is conveyed to the filter 5 for filtration. The output end of the filter 5 is connected to the clear water tank 6, so that the filtered clear water is temporarily stored in the clear water tank 6. The clear water tank 6 is equipped with a liquid constant temperature cooler 7 to control the temperature of the clear water in the clear water tank 6. The clear water tank 6 is connected to the accumulator 9 through the second conveying pump 8 to stabilize the pressure. The accumulator 9 is connected to the pressure regulating valve 10 to control the output pressure of the clear water.

[0020] Because the wastewater after preliminary filtration contains a large number of ultrafine particles with a diameter of 0.01μm, it is difficult to directly intercept them by relying solely on the sieving effect of the filter medium. Therefore, this invention uses a powder adding machine 2 to add diatomaceous earth powder to the wastewater tank 1, and uses a powder mixing mechanism 3 to fully mix the diatomaceous earth powder and wastewater. Then, it uses a stacked plate and frame filter press with a built-in precision filter membrane for filtration. The diatomaceous earth powder can play the following dual role: 1. Adsorption, bridging, and agglomeration: Due to the rich porous microstructure and huge specific surface area of ​​diatomaceous earth powder, it can capture ultrafine suspended particles of 0.01μm in sewage through physical adsorption. At the same time, diatomaceous earth powder acts as a crystal nucleus, causing a large number of submicron and nano-sized particles to agglomerate with each other, thereby forming larger flocs (i.e., agglomerates). In this way, ultrafine particles that originally easily penetrate the filter material will be fixed inside the agglomerates, thus eliminating the problem of ultrafine particles penetrating the filter material. 2. Formation of dynamic filter cake layer: When the mixed liquid carrying agglomerates is transported to a stacked plate and frame filter press with a built-in precision filter membrane, the diatomaceous earth powder in the mixed liquid will continuously deposit on the surface of the precision filter membrane, thereby forming a dynamic filter cake layer with submicron-level pores.

[0021] Meanwhile, the precision filter membrane of the stacked plate and frame filter press serves as the basic support medium. The basic interception accuracy of the precision filter membrane itself is insufficient to intercept ultrafine particles of 0.01μm. Its main function is to support diatomaceous earth powder and retain agglomerated flocs. During the operation of the filter press 5, the continuously accumulated dynamic filter cake layer can constitute a secondary precision filter layer. Because the internal micropores of the dynamic filter cake layer are much smaller than the original pore size of the precision filter membrane, the synergistic combination mechanism of the precision filter membrane screening + the deep interception of the dynamic filter cake layer + the pre-adsorption and agglomeration of ultrafine particles can effectively achieve stable interception of ultrafine particles of 0.01μm, so that the overall filtration accuracy reaches 0.01μm.

[0022] In some embodiments of this utility model, the sewage purification device 100 further includes a first level gauge 11 disposed in the sewage tank 1 and a second level gauge 12 disposed in the clean water tank 6, both of which are used to detect the liquid level.

[0023] In a preferred embodiment of this utility model, the filter 5 is a stacked plate and frame filter with a built-in high-polymer precision filter membrane with a nominal precision of 0.1μm; the stacked plate and frame filter is also known as a multi-layer filter, which is a precision filtration device; the high-polymer precision filter membrane can specifically be a polypropylene filter membrane or a PTFE filter membrane.

[0024] In a preferred embodiment of this invention, the second delivery pump 8 is a cooling water pump. Cooling water pumps are suitable for conveying clean water or liquids with physicochemical properties in high-pressure operating systems, and can increase the working pressure of the coolant in the circulating system. In a specific implementation, the second delivery pump 8 can deliver clean water from the clean water tank 6 to the accumulator 9 at high pressure (maximum pressure 100 bar) for pressure stabilization.

[0025] In a preferred embodiment of this utility model, the first delivery pump 4 is a diaphragm pump. A diaphragm pump is a positive displacement pump that transports liquids through the reciprocating deformation of a diaphragm. Its most significant feature is that the working medium is completely isolated from the transmission components, making it suitable for transporting corrosive, particulate, or high-viscosity liquids. Because the sewage in the sewage tank 1 contains particulate matter such as diatomaceous earth powder, a diaphragm pump is used to transport the sewage in the sewage tank 1 to the filter 5.

[0026] In some embodiments of this utility model, the lower end of the sewage tank 1 is provided with a drain port 102, and the upper end of the sewage tank 1 is provided with an overflow port 103. The drain port 102 is used for sewage discharge operation when cleaning the sewage tank 1, and is normally closed during normal use. The overflow port 103 is used to discharge sewage when the liquid level in the sewage tank 1 is too high, and is normally open.

[0027] Please refer to the following embodiments of this utility model. Figures 2 to 4 As shown, the sewage tank 1 and the clean water tank 6 share a main body 13. The main body 13 is divided into two independent storage spaces by a partition 131. One independent storage space serves as the sewage tank 1, and the other as the clean water tank 6. This invention, by designing the sewage tank 1 and clean water tank 6 to share a main body 13, makes the entire sewage purification device 100 more compact, aesthetically pleasing, and space-saving. Of course, the above is only a preferred embodiment of this invention, but it is not limited to this. In specific implementations, the sewage tank 1 and the clean water tank 6 can also be set up separately, such as... Figure 1 As shown.

[0028] In some embodiments of this utility model, the powder mixing mechanism 3 includes a drive motor 301, a mixing blade 302, and a mixing shaft 303. The drive motor 301 is located above the sewage tank 1, the mixing blade 302 is located in the lower middle part of the sewage tank 1, the upper end of the mixing shaft 303 is connected to the output end of the drive motor 301, and the lower end of the mixing shaft 303 is connected to the mixing blade 302. During operation, the drive motor 301 drives the mixing shaft 303 to rotate the mixing blade 302, so that the mixing blade 302 can mix the diatomaceous earth powder and sewage in the sewage tank 1.

[0029] In some embodiments of this utility model, the wastewater purification device 100 further includes a control cabinet 14; the powder feeder 2, powder mixing mechanism 3, first conveying pump 4, filter 5, liquid constant temperature cooler 7, second conveying pump 8, and pressure regulating valve 10 are electrically connected to the control cabinet 14 so that the control cabinet 14 can be used to power and control each device. Simultaneously, the first level gauge 11 and the second level gauge 12 also need to be electrically connected to the control cabinet 14. Of course, for the powder feeder 2, pressure regulating valve 10, etc., if manual control is used, it is not necessary to electrically connect them to the control cabinet 14; electrical connection is only required when automatic control is used. In specific implementations of this utility model, the control cabinet 14 can be placed on top of the main housing 13. Alternatively, the control cabinet 14 can be independently placed next to the main housing 13, depending on actual needs.

[0030] The overall working principle of the wastewater purification device 100 of this utility model is as follows: Wastewater generated during the processing of the machining center and after preliminary filtration is sent into the wastewater tank 1 through a pipe (not shown) from the wastewater inlet 101. The preliminary filtration mainly involves filtering particulate impurities from the wastewater generated during the processing of the machining center through filter bags, filter cotton, sedimentation tanks, etc. The powder feeder 2 adds diatomaceous earth powder to the sewage tank 1 at regular intervals, and controls the powder mixing mechanism 3 to mix the diatomaceous earth powder and sewage in the sewage tank 1. At the same time, the first liquid level gauge 11 detects the liquid level in the sewage tank 1 in real time. When the liquid level is insufficient, it can prompt the processing center to add water or trigger an alarm. When the liquid level is too high, it prompts the processing center to stop adding water. Excess sewage can be automatically discharged through the overflow port 103. The first transfer pump 4 is used to transport the mixed sewage in the sewage tank 1 to the filter 5 for filtration, and the filtered clean water is then transported to the clean water tank 6 for temporary storage. The liquid constant temperature cooler 7 is used to control the temperature of the clean water in the clean water tank 6 to ensure that the clean water temperature is constant. At the same time, the second liquid level gauge 12 is used to detect the liquid level in the clean water tank 6 in real time. When the liquid level is detected to be insufficient, the first transfer pump 4 and the filter 5 are controlled to work to replenish the clean water tank 6. When the liquid level is detected to be too high, the first transfer pump 4 and the filter 5 are controlled to stop working. The clean water in the clean water tank 6 is delivered to the accumulator 9 by the second delivery pump 8 for pressure stabilization, and the outlet water pressure is controlled by the pressure regulating valve 10 (for example, the outlet water pressure is controlled at 70 bar), thereby realizing the stable output of clean water. The output clean water can be used for micro-hole drilling.

[0031] In summary, this utility model utilizes a powder feeder 2 to add diatomaceous earth powder to a wastewater tank 1, and a powder mixing mechanism 3 to mix the diatomaceous earth powder and wastewater in the wastewater tank 1. Then, a first pump 4 transports the mixed wastewater to a stacked plate and frame filter press for filtration, achieving a filtration level of 0.01µm. Simultaneously, the clean water in the clear water tank 6 is kept at a constant temperature using a liquid constant temperature cooler 7, and the output clear water first passes through an accumulator 9 for pressure stabilization, and then the pressure is controlled by a pressure regulating valve 10. Therefore, through the above technical solution of this utility model, reliable filtration of wastewater generated during microporous processing can be effectively achieved, ensuring that the filtered clear water quality, temperature, and pressure meet the requirements for use with microporous drilling bits.

[0032] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A wastewater purification device for semiconductor micropore fabrication, characterized in that, The system includes a wastewater tank, a powder feeder, a powder mixing mechanism, a first conveying pump, a filter, a clean water tank, a liquid constant-temperature cooler, a second conveying pump, an accumulator, and a pressure regulating valve. The wastewater tank has a wastewater inlet. The powder feeder is located outside the wastewater tank, with its output connected to the inside of the wastewater tank. The wastewater tank is equipped with a powder mixing mechanism and is connected to the filter via the first conveying pump. The output of the filter is connected to the clean water tank, which is equipped with a liquid constant-temperature cooler. The clean water tank is connected to the accumulator via the second conveying pump, and the accumulator is connected to the pressure regulating valve. The filter is a stacked plate and frame filter with a built-in precision filter membrane. The powder feeder is used to add diatomaceous earth powder, which has adsorption, bridging, and agglomeration effects, and forms a dynamic filter cake layer on the surface of the precision filter membrane of the filter, into the wastewater tank.

2. The wastewater purification device for semiconductor micropore processing according to claim 1, characterized in that, It also includes a first level gauge installed in the sewage tank and a second level gauge installed in the clean water tank.

3. The wastewater purification device for semiconductor micropore processing according to claim 1, characterized in that, The filter is a stacked plate and frame filter with a built-in high-precision polymer filter membrane with a nominal precision of 0.1μm.

4. The wastewater purification device for semiconductor micropore processing according to claim 1, characterized in that, The second delivery pump is a cooling water pump.

5. The wastewater purification device for semiconductor micropore processing according to claim 1, characterized in that, The first delivery pump is a diaphragm pump.

6. The wastewater purification device for semiconductor micropore processing according to claim 1, characterized in that, The sewage tank has a drain outlet at the bottom and an overflow outlet at the top.

7. The wastewater purification device for semiconductor micropore fabrication according to claim 1, characterized in that, The sewage tank and the clean water tank share a main tank, which is divided into two independent storage spaces by a partition. One independent storage space serves as the sewage tank, and the other independent storage space serves as the clean water tank.

8. The wastewater purification device for semiconductor micropore processing according to claim 1, characterized in that, The powder mixing mechanism includes a drive motor, mixing blades, and a mixing shaft. The drive motor is located above the sewage tank, the mixing blades are located in the lower middle part of the sewage tank, the upper end of the mixing shaft is connected to the output end of the drive motor, and the lower end of the mixing shaft is connected to the mixing blades.

9. A wastewater purification device for semiconductor micropore fabrication according to any one of claims 1-8, characterized in that, It also includes a control cabinet; the powder feeder, powder mixing mechanism, first conveying pump, filter, liquid constant temperature cooler, second conveying pump and pressure regulating valve are electrically connected to the control cabinet.

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